Apparatus for the manufacture of a second cross-fold on folding devices of rotary printing machines



April 14, 1970 A. JAHN El'AL 3,506,255

APPARATUS FOR THE MANUFACTURE OF A SECOND CROSS-FOLD on FOLDING DEVICES OF ROTARY PRINTING MACHINES Filed June 7, 1967 INVENTORS ARTHUR JAHN HORST THEER ATTORNEY.

United States Patent 3,506,255 APPARATUS FOR THE MANUFACTURE OF A SECOND CROSS-FOLD 0N FOLDING DE- VICES 0F ROTARY PRINTING MACHINES Arthur Jahn and Horst Theer, Bohlitz-Ehrenberg, Germany, assignors to VEB Druckmaschiuenwerke Leipzig, Leipzig, Germany, a corporation of Germany Filed June 7, 1967, Ser. No. 644,366 Int. Cl. B65h 45/16 US. Cl. 27072 2 Claims ABSTRACT OF THE DISCLOSURE An apparatus for producing a second cross-fold of a web in folding devices of roller-rotation printing machines, in which two-fold-knife-cylinders are coordinated to one fold-fiap-cylinder, wherein a product, which has a first cross-fold, is pressed down closely on the fold-flap cylinder by means of wide straying blow-air rays. Then a second cross-fold is formed on the product and the first cross-fold is shortly thereafter released and the front edge of the product is turned by means of a wide air stream.

The present invention relates to an apparatus for the manufacture of a second cross-fold of a web in folding devices of rollers-rotary printing machines.

In these machines the print carrier is removed from the roller, then guided mostly through a plurality of printing attachments and other auxiliary units and after termination of the print folded longitudinally over the funnel folder, and cut in sheets and webs, respectively, and then fed to cross folding devices, for instance cylinder folding devices.

Cylinder folders are known in which two folding knives are coordinated to one fold flap cylinder, that means that the second cross-fold is produced on the same cylinder on which the first cross-fold has been produced. The front edge of the first fold is taken up and turned in this device by means of grippers or the like, which are mounted in the fold knife cylinder. By this arrangement, the drawback results, that already prior to the insertion of the second cross-fold a bubble formation between the web and the fold cylinder is created at the point, which is disposed between the first cross-fold and the flaps for the second fold. This leads to inexactnesses which cannot be tolerated.

It was for this reason, that in the practice the use of a single fold cylinder has been abandoned if, as it is used in the package industry, greater exactness is desired. These requirements are met by embodiments in accordauce with the following arrangements:

After the web is folded longitudinally over one or a plurality of funnel folders, it is guided over corresponding draw-in devices between the cutting device and is there separated.

The counter cylinder to the cutting cylinder is thereby mostly simultaneously equipped with one or a plurality of folding knives, so that the longitudinally folded and cut sheet is taken up in the fold flaps of a fold-flap cylinder. Upon closing of these fold flaps, the grippers or the like of the second fold-knife cylinder are released from their working position, so that the sheet or better expressed the final product having a first cross-fold is taken up by the foldflap cylinder. In order to obtain now a second cross-fold, disposed parallel to the first fold, it is operated such, that again a fold-knife cylinder is coordinated to this fold-flap cylinder and a second fold-flap cylinder is coordinated to the fold-knife cylinder. This structural unit performs the same operations, as stated in connection with the first cross fold. These arrangements have the advantage, that they operate reliably and with great exactness. It is, however, a drawback that totally five cylinders must be mounted in series with a relatively great space requirement. This is felt in particular, if in addition to the previously mentioned cylinders still a collecting cylinder is disposed intermediate thereof.

It has been also known to choose the arrangement of the cylinders of folding devices on roller rotary printing machines such, that the sheets arriving from the cuttingknife cylinder are taken up from the cylinder folding device nearly without exception without the previously conventional sheet guide means as grippers and the like. The fact is exploited thereby, that the sheets are anyway held by the fold flaps. Fold knives are coordinated also to the fold flap cylinder for the first cross-fold, which fold knives guide the web into the fold flaps of a second fold flap cylinder.

It is one object of the present invention to provide an apparatus for the manufacture of a second cross-fold in a web on folding devices of rotary printing machines wherein the mentioned drawbacks are avoided and a robust space-saving double parallel folding device is created which assures the required exactness.

It is another object of the present invention to provide an apparatus for the manufacture of a second cross-fold in webs on folding devices of rotary printing machines, by which the fold products are equipped with two crossfolds while the required exact tolerances are maintained, whereby the advantage to perform both on the same fold-flap cylinder is to be retained. Furthermore, with the help of the apparatus of the present invention it is possible, to manage with a minimum of controlled machine elements and to avoid that the webs to the second cross-fold are subjected to a directional variation, and a transfer to a second cylinder, respectively, must take place.

It is still another object of the present invention to provide an apparatus for the manufacture of a second cross-fold of webs on folding devices of rotary printing machines, by which the web equipped with the first crossfold can be pressed closely to the fold-flap cylinder by means of laterally straying blow air streams and by means of at least one blank holder. Then the second cross fold can be performed on the same fold-flap cylinder, and only shortly thereafter the first cross flap is released and then the front edge of the web is turned by a strikershaped air stream. The finished web can then be transferred directly to the known delivery devices. It is another object of the present invention to provide for the suitable performance of the making of the second crossfold by providing an apparatus in which particularly a blow ledge including a plurality of rows of blowing nozzles extending over the entire width of the web is provided laterally between the fold-flap cylinder and the fold knife cylinder secured to a blank holder adjustable as to its distance from the fold-flap cylinder or separately to the machine frame. A second blow ledge is arranged at a variable distance therefrom, which second blow ledge has one row of nozzles extending over the total width of the material web.

With these and other objects in view, which will become apparent in the following detailed description, the present invention will be clearly understood in connection with the accompanying drawing, in which the only figure discloses a schematic elevation of the portion of the fold apparatus producing the second cross-fold, shortly prior to the termination of the closing of the fold flap for the second cross fold.

Referring now to the drawing, the apparatus designed in accordance with the present invention comprises a cuttingand fold-knife cylinder 1. A sheet or web 2, previously removed from the material web, is received in known manner between fold flaps 3 and the fold flap abutments 4 and thereby the first cross fold A is formed. Additional fold flaps 6 and fold flap abutments 7 are provided on the fold-flap cylinder between the fold flaps 3 arranged for the first cross-fold A and the fold flap abutments 4.

Seen in the direction of movement of the sheet 2, indicated by the arrows a and n, a blank holder 10 adjustable as to its distance to the fold flap cylinder 5 is provided shortly behind a fold knife cylinder 8, which carries one or a plurality of fold knives 9. Either on the blank holder 10 or on the machine frame (not shown) is arranged a blow ledge 11 having a plurality of rows of blow nozzles such, that laterally straying blow air streams 13 press the sheet 2 between the fold flaps 3 for the first cross-fold A and those for the second cross-fold B, over nearly the entire line, to the fold-flap cylinder 5. As soon as the sheet 2 is received between the fold flaps 6 and the fold-flap abutments 7, the fold flaps 3 are opened by conventional means. In variable distance in front of these fold flaps 3 is in a tangential direction towards the fold-flap cylinder 5 another blow ledge 14. By a row of nozzles 15 a striking air stream 16 is produced by means of which the change of direction of the forward edge of the product 2 is brought about.

The exactness of the second cross-fold is obtained by means of the blank holder 10 and the blow air streams 13, whereby the sheet 2 is applied, as tight as possible to the fold-fiap cylinder 5. The blank holder 10 can be arranged such, that it extends over the total width of the material web. It can, however, be formed also of a plurality of individual members divided over the entire width of the material web. Furthermore, it is also possible to arrange these members set off relative to each other.

In addition to the advantages set forth above, the advantage is also brought about that in the arrangement according to the present invention there is no necessity to control the blow air streams 13 or the flowing blow air stream 16. Rather it is possible without difficulty to permit a continuous operation of the blow air stream already available in the apparatus of the present invention.

While we have disclosed one embodiment of the present invention, it is to be understood that this embodiment is given by example only and not in a limiting sense, the scope of the present invention being determined by the claims.

We claim:

1. An apparatus for producing a second cross-fold of a web in folding devices of roller-rotation printing machines, comprising a machine frame,

a fold-flap cylinder means rotatably mounted in said machine frame,

a cuttingand fold-knife cylinder means operatively rotatably engaging said fold-flap cylinder means and rotatably mounted in said machine frame,

a second fold-knife cylinder means operatively rotatably engaging, at spaced position from said cuttingand fold-knife cylinder means, said fold-flap cylinder means and rotatably mounted in said machine frame,

said cylinder means cooperatively adapted so that portions of a web move between said fold-flap cylinder means and one of said cuttingand fold-knife cylinder means and said second fold-knife cylinder means, respectively, in that order,

said cuttingand fold-knife cylinder means and said second fold-knife cylinder means, respectively, in cooperation with said fold-flap cylinder means for producing a first cross-fold on said web adjacent a forward edge of said web and a second cross-fold spaced therefrom on said web, respectively, in that order,

said fold-flap cylinder means including means for releasably holding said forward edge of said web thereto,

at least one blank holder disposed adjacent to and ahead, with respect to the direction of movement of said web, of said second fold-knife cylinder means and adjacent said fold-flap cylinder means,

a first blow ledge means disposed ahead of said second fold-knife cylinder means for directing air streams onto said web adjacent thereto on said fold-flap cylinder means,

said first 'blow ledge means and said at least one blank holder for pressing said web having said first crossfold against said fold-flap cylinder means, between said second fold-knife cylinder means and said releasable holding means, and

a second blow ledge disposed further ahead of said first blow ledge in the direction of movement of said web and directing an air stream strikingly onto said forward edge adjacent said first cross-fold of said web causing said forward edge to change its direction of movement upon a release of said first cross-fold from said releasable holding means.

2. The apparatus, as set forth in claim 1, wherein said second blow ledge is adjustable and causes the lifting of said web at said forward edge from said fold-flap cylinder means.

References Cited UNITED STATES PATENTS 2,229,487 1/ 1941 Barber 270-72 3,337,211 8/1967 Blcane 270-76 FOREIGN PATENTS 33,320 11/1964 Germany.

EUGENE R. CAPOZIO, Primary Examiner P. V. WILLIAMS, Assistant Examiner US. Cl. X.R. 270-69 

